My OB improved by chance. Using up some green spray paint on the backs I re-did the crossover. The 12 Lta has double tags. This was enough to mount most of the crossover which is minimal. It sounds better than on tag strip. Subtle, but in the right way. Slightly more mid band control. It is by chance star ground and almost star hot. The hot being a silver plated OFC offcut about 1 1/2 inches long. As the amp is capacitor coupled I use a DIN plug to keep 34 VDC confined. The coupling is 4700 uF 1200 uF and 3 uF to the hot bar ( Quad 303 to the transistor outputs ) . The only crossover is a 3.5 mH choke to the 15 inch unit ( 5R 7 ). Then some EQ from upgraded Quad 33 preamp.
I haven't bothered going far on the midband taming. One day I intend building an active version. I will borrow my friends PA set up to the ideal frequencies and rates of cut. Until then I feel I am 90 % OK with what I have. I won't use measuring equipement as recent experiance shows it can cause more problems than it solves. It seems like taking a pill because one takes another pill. before you know it 24 pills to take. That forest stops the amplifier controling the driver. The amp never sees a direct path. What I also learned is that sound is always there if a resonance.
If active it is the salt and pepper one can add. Unlike food we can add or subtract in an instant. I will build the filters into the amplifers. That way the complexity is kept minimal . Passive where possible. I hope for a mix of valves and transistors. The bass 250 watts and the upper bass to lower treble 8 to 20 watts valve. Treble might be class A transistor. If a JLH the output cap is also the filter. The tweeter is form >7 kHz.
I haven't bothered going far on the midband taming. One day I intend building an active version. I will borrow my friends PA set up to the ideal frequencies and rates of cut. Until then I feel I am 90 % OK with what I have. I won't use measuring equipement as recent experiance shows it can cause more problems than it solves. It seems like taking a pill because one takes another pill. before you know it 24 pills to take. That forest stops the amplifier controling the driver. The amp never sees a direct path. What I also learned is that sound is always there if a resonance.
If active it is the salt and pepper one can add. Unlike food we can add or subtract in an instant. I will build the filters into the amplifers. That way the complexity is kept minimal . Passive where possible. I hope for a mix of valves and transistors. The bass 250 watts and the upper bass to lower treble 8 to 20 watts valve. Treble might be class A transistor. If a JLH the output cap is also the filter. The tweeter is form >7 kHz.
This is why I prefer no crossovers in my system.
I use a pair of Fane 12-250TC with a Fane 15-600LF. They seem to work well together.
That reminds me of PA rigs although they are sealed boxes. I think Meyer even have angle calcualtions for each box ( and displacement ) and each venue?
I made a crude phase plug for my similar 12 Lta. It is a 4 x 1 inch foam paint roller. It is held on a 1930's style curtain spring so as to just clear the cone strung from the 12 to 6 o'clock fixings. This means I can take it off in seconds and have a standard driver. It is good enough to say how it could work. Better and worse. The original has more bight. I dare say it is too long and EQ needed. It also sounds very sweet and voices seem better. I shall repeat the idea with 12 inch wood ruler and broom handle stub. I might put a small soft foam damper between wood and cone mostly as an air seal. As far as I can see this is no worse than a standard phase plug.
I made a crude phase plug for my similar 12 Lta. It is a 4 x 1 inch foam paint roller. It is held on a 1930's style curtain spring so as to just clear the cone strung from the 12 to 6 o'clock fixings. This means I can take it off in seconds and have a standard driver. It is good enough to say how it could work. Better and worse. The original has more bight. I dare say it is too long and EQ needed. It also sounds very sweet and voices seem better. I shall repeat the idea with 12 inch wood ruler and broom handle stub. I might put a small soft foam damper between wood and cone mostly as an air seal. As far as I can see this is no worse than a standard phase plug.
Maybe 7hrs on it.
On floor 11' away, not much below 100hz.
Run off an rca plug DVD player into 10 band eq.
+3@30hz/60hz. -3db@120hz. -6db@1khz/2khz/4khz. -3db@16khz
Just 1 speaker.
Bryan Adams........ Good
Diana Krall wallflowers cd track 6+.......... Great
Jefferson airplane/starship hits.......... Good
"Big times in a small town"......... Great
Fight club soundtrack............. Not bad at all
Battle star Galactica............ Really good (surprising, but voices from floor)
Gun's and Roses gold CD.......... Really bad.
Frank Sinatra " witchcraft" from 50 shades movie CD........ Magical
Definitely a fun relatively inexpensive driver.
I look forward to more people playing with them.
Norman
On floor 11' away, not much below 100hz.
Run off an rca plug DVD player into 10 band eq.
+3@30hz/60hz. -3db@120hz. -6db@1khz/2khz/4khz. -3db@16khz
Just 1 speaker.
Bryan Adams........ Good
Diana Krall wallflowers cd track 6+.......... Great
Jefferson airplane/starship hits.......... Good
"Big times in a small town"......... Great
Fight club soundtrack............. Not bad at all
Battle star Galactica............ Really good (surprising, but voices from floor)
Gun's and Roses gold CD.......... Really bad.
Frank Sinatra " witchcraft" from 50 shades movie CD........ Magical
Definitely a fun relatively inexpensive driver.
I look forward to more people playing with them.
Norman
Huh.
I think they are showing different wait times based on ISP addresses (how often you look at them).
My buddy ordered mine (with 10% discount coupon).
His mcm screen and cart showed 87 days out, while my CPU at work (last week) showed 8 days (and cart).
My tablet says 77 days now.
They will fill the full retail orders first, then the 10% offers after I bet.
If I have to wait 2 months, I may see about not getting them and work on a push-pull sealed rs390hf (f3 around 30hz, f8 20hz). Should with 400 watts do 108db@20hz not skipping past xmax.
Norman
I think they are showing different wait times based on ISP addresses (how often you look at them).
My buddy ordered mine (with 10% discount coupon).
His mcm screen and cart showed 87 days out, while my CPU at work (last week) showed 8 days (and cart).
My tablet says 77 days now.
They will fill the full retail orders first, then the 10% offers after I bet.
If I have to wait 2 months, I may see about not getting them and work on a push-pull sealed rs390hf (f3 around 30hz, f8 20hz). Should with 400 watts do 108db@20hz not skipping past xmax.
Norman
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